In recent years, there have been proposed various illumination devices using light-emitting diodes (hereinafter referred to as “LEDs”) as light-emitting elements (see Patent Documents 1 to 3). This type of illumination device has a problem that while the device is driven, heat generated from the LEDs tends to stay in the device. If the heat stays in the device, the lifetime of the LEDs is affected. In order to cope with this problem, in Patent Document 1, light-emitting elements are mounted on an upper surface of a board having a heat transfer function and the board is supported by a radiator, thereby expecting that heat in a device is effectively dissipated to the outside through the board and the radiator.
Referring to FIG. 14, the technique disclosed in Patent Document 1 will be briefly described. In a LED bulb lamp shown in FIG. 14, an LED board 2 and a globe 3 covering it are attached to a radiator 1 on its one end side and a receiving case 6 receiving therein a lighting device 5 is attached to the radiator 1 on its other end side. A base 7 is attached to the receiving case 6. The LED board 2 is provided on its one surface side with a plurality of LEDs 8 and a connector receiving portion 9. The connector receiving portion 9 is provided at a central portion of the LED board 2 and is connected to the lighting device 5 via a power feeder 12 which is inserted through a wiring hole 11 penetrating the LED board 2 in the vicinity of the connector receiving portion 9. In this manner, power can be supplied to the LEDs 8 through the power feeder 12 and the connector receiving portion 9.